Boundary layer carbonation of trona
A boundary layer carbonation process for producing sodium bicarbonate crystals having specific surface area in the range 0.4 m 2 /g to 2.5 m 2 /g from Trona, wherein in one embodiment the process comprises the steps of: providing Trona particles having a particle size range of −4+120 mesh; pre-wetting the Trona particles with water to provide a plurality of pre-wetted Trona particles each having a liquid water solution boundary layer deposited thereon; and carbonating the pre-wetted Trona particles across the water boundary layer to provide a product comprising sodium bicarbonate crystals.
1. A process for converting a sodium carbonate containing ore into sodium bicarbonate, the process comprising:
adding the sodium carbonate containing ore to a reactor vessel in the form of particles having a size range of 1 micron to 4,000 microns;
adding CO 2 to the reactor vessel; and
reacting the particles of the sodium carbonate containing ore with the CO 2 in the presence of water via boundary layer carbonation while providing mixing that is sufficient to counter agglomeration of the particles of the sodium carbonate containing ore and thus form a reacted composition comprising sodium bicarbonate having a surface area between 0.4 m 2 /g and 2.5 m 2 /g with a conversion of 25% to 100%.
2. The process according to claim 1 , wherein the sodium carbonate containing ore comprises Trona.
3. The process according to claim 1 , wherein the particles of the sodium carbonate containing ore have a size range of 37 to 500 microns.
4. The process according to claim 1 , wherein reacting comprises forming a liquid water film around the particles.
5. The process according to claim 1 , wherein the reacting is carried out at a temperature of about 125° F. to about 185° F.
6. The process according to claim 1 , wherein said mixing comprises predominately radial mixing.
7. The process according to claim 1 , wherein said mixing is sufficient to prevent CO 2 bulk transfer from being the boundary layer carbonation rate limiting step.
8. The process according to claim 1 , further comprising removing excess water from the reaction by removing water from a CO 2 containing recycle stream.
9. The process according to claim 8 , comprising directing the CO 2 containing recycle stream to a demister.
10. The process according to claim 9 , wherein, prior to said step of directing the CO 2 containing recycle stream to a demister, further comprising directing the CO 2 containing stream to a heat exchanger.
11. The process according to claim 8 , further comprising directing the CO 2 containing recycle stream through a dust collector.